1. Field of the Invention
The present invention relates to a card connection adaptor for connecting an IC card such as a memory card or a functional extension card to an information system such as a personal computer, or a portable information system represented by a PDA (personal digital assistant), a digital still camera and a digital video camera.
2. Description of Related Art
Recent notebook PCs (personal computers) are generally equipped with PC card slots. Functional extension of such a notebook PC can be achieved by inserting a PC card into the PC card slot. Exemplary PC cards include flash memory cards, modem cards and SCSI cards.
The PC cards are designed in compliance with the PC Card Standard, and classified into three types which have thicknesses of 3.3 mm (Type I), 5.0 mm (Type II) and 10.5 mm (Type III), respectively, with a rectangular plan shape of 54.0-mm width and 85.6-mm length.
For smaller-size information systems such as digital cameras, electronic organizers and portable phones, smaller-size CF (CompactFlash (registered trade mark)) cards are employed instead of the PC cards to meet a heavy demand for size reduction. Typical examples of the CF cards are flash memory cards which are employed to store image data picked up by digital cameras and schedule data and address data for electronic organizers.
The CF cards are designed in compliance with the CFA (CompactFlash Association) Standard and classified into two types which have thicknesses of 3.3 mm (Type I) and 5.0 mm (Type II), respectively, with a rectangular plan shape of 36.4-mm width and 42.5-mm length.
Further, the digital cameras, digital voice recorders and portable phones employ small-size memory cards adapted only for memory functions. Such a small-size memory card includes a memory IC die packaged by resin-sealing, and is characterized by its extremely small thickness. Examples of the memory cards include SmartMedia cards (SSFDCs: solid state floppy disk cards), Miniature cards, MemoryStick cards and MultiMedia cards.
These cards have outer dimensions as shown below.
SmartMedia (SM): 37xc3x9745xc3x970.76 (mm)
Miniature card (MC): 38xc3x9733xc3x973.5 (mm)
MemoryStick (MS): 50xc3x9721.5xc3x972.8 (mm)
MultiMedia card (MMC): 32xc3x9724xc3x971.4 (mm)
Since the smaller-size information systems do not always have sufficient data processing power, it is often necessary to load image data picked up by a digital camera into a notebook PC or to transfer data between an electronic organizer and a notebook PC.
However, when data retained in the small-size information system are to be loaded into the notebook PC via a CF card or a small-size memory card, for example, such a card cannot directly be fitted in the PC card slot of the notebook PC because the PC card slot is designed in compliance with the PC Card Standard.
Therefore, card connection adaptors are conventionally provided for connecting a CF card or a small-size memory card to a PC card slot.
Such a card connection adaptor includes a housing having a shape conformal to the PC card, a first connector provided on a front side of the housing for connection to a PC card slot, and a second connector provided within the housing for connection to a CF card or a small-size memory card. A card retaining space for receiving the CF card or the small-size memory card is provided within the housing. The card retaining space opens into a rear face of the housing as seen in an insertion direction in which the card connection adaptor is inserted into the PC card slot. Where the small-size card has a thickness close to the thickness of the card connection adaptor, the card retaining space may also open into the upper and/or lower side of the housing. In any case, the small-size card is inserted into the card connection adaptor from the rear side of the card connection adaptor in the same direction as the insertion direction in which the card connection adaptor is inserted into the PC card slot.
However, this arrangement has drawbacks from mechanical and electrical viewpoints. More specifically, when the card connection adaptor is fitted in the PC card slot, a rear portion of the small-size card fitted in the card connection adaptor is exposed from an opening of the PC card slot. Hence, there is a possibility that the small-size card is disconnected from the card connection adaptor by some external force. If the small-size card is disconnected during data transfer between an information system and the small-size card, the data transfer is of course failed, and destruction of date or destruction of elements inside the small-size card may result from erroneous signal input. This is particularly problematic in the case of a card which is designed to lead signal input/output interconnections from the small-size card (e.g., GSM card). Further, it is difficult to provide a lock holder in the card connection adaptor for assuredly holding the small-size card, whereas it is easy to provide a holder mechanism in a PC card slot for holding a card inserted therein.
Since it is physically possible to insert the small-size card into the card connection adaptor from the rear side thereof with the card connection adaptor fitted in a PC card slot, a user may make an attempt to insert the small-size card into the card connection adaptor in this sate. In such a case, a great external force is exerted onto the connector of the PC card slot, so that the connector may be damaged.
In addition, there is a possibility that the small-size card is inserted into or withdrawn from the card connection adaptor fitted in a PC card slot when the information system is energized. Therefore, in designing the card connection adaptor, a consideration should be given to prevent the small-size card from being damaged by so-called active card insertion and withdrawal. More specifically, connection terminals of the card connection adaptor should accurately be positioned so that the connection/disconnection orders and connection/disconnection timings for connection and disconnection of connection terminals of the small-size card with respect to the connection terminals of the card connection adaptor can be kept substantially constant when the small-size card is inserted into or withdrawn from the card connection adaptor. When the small-size card is to be inserted into the card connection adaptor, for example, connection of a grounding terminal, a source terminal, a first signal terminal, a second terminal and so forth should be established in the order named within an allowable connection timing range. It is, therefore, extremely difficult to design the card connection adaptor which can offer a guarantee against the active insertion and withdrawal.
It is a first object of the present invention to provide a card connection adaptor which is capable of preventing disconnection of a small-size card therefrom when the adaptor is fitted in a card slot, thereby having an improved reliability.
It is a second object of the present invention to provide a card connection adaptor which is capable of prohibiting a small-size card from being inserted thereinto or withdrawn therefrom when the adaptor is fitted in a card slot, thereby having an improved reliability and a simplified construction.
It is a third object of the present invention to provide a card connection adaptor which is constructed so as to be able to give an indication of the presence or absence of a small-size card in the adaptor when the adaptor is fitted in a card slot.
In accordance with one aspect of the present invention, there is provided a card connection adaptor for connecting to a connector of a card slot compliant with a predetermined first standard, a card compliant with a second standard which is different from the first standard, the card connection adaptor comprising: a first connector compliant with the first standard and adapted to be electrically connected to the connector of the card slot; a second connector compliant with the second standard; signal conversion circuitry connected to the first connector and the second connector for performing signal conversion between a first-standard-compliant signal and a second-standard-compliant signal; and a housing which holds the first connector, the second connector and the signal conversion circuitry, the housing having a card insertion port which opens in a direction generally perpendicular to an adaptor insertion direction in which the card connection adaptor is inserted into the card slot, and a card retaining space for retaining therein the second-standard-compliant card inserted from the card insertion port.
The card connection adaptor preferably has a card shape conformal to the first-standard-compliant card slot. That is, the housing preferably has a card-like exterior configuration which is conformal to a first-standard-compliant card. In this case, xe2x80x9cthe direction generally perpendicular to the adaptor insertion directionxe2x80x9d is preferably a direction parallel to upper and lower faces of the card-shaped adaptor.
The first connector is preferably provided on a face of the adaptor to be opposed to the connector of the card slot.
The second connector is preferably provided in such a position that the second connector can be brought into contact with terminals of the second-standard-compliant card retained in the card retaining space.
It is preferred that the card retaining space does not open into a rear face of the adaptor as seen in the adaptor insertion direction. That is, at least the rear side of the card retaining space is preferably closed so that the second-standard-compliant card cannot be inserted or withdrawn from the rear side.
The connector of the card slot is preferably adapted to be contact-connected to the first connector.
The card connection adaptor may be powered via the connector of the card slot and the first connector. In this case, the second-standard-compliant card may be powered from the card connection adaptor.
The card slot may be a PC-standard memory card slot. In this case, the PC-standard memory card slot means a card slot which may commonly be provided in a PC. Examples of such a card slot include those which are compliant with the PC Card Standard and the CF Card Standard. These standards stipulate that an input/output control circuit for controlling data input and output be provided in the card. Examples of such an input/output control circuit include those which are adapted to control writing and reading of data with respect to a memory IC incorporated in the card.
The card retaining space is preferably configured so as not to allow the second-standard-compliant card to project outwardly of the card retaining space when the card is retained in the card retaining space.
The card connection adaptor may further include a wiring board provided within the housing, wherein the first connector, the second connector and the signal conversion circuitry are mounted on the wiring board.
The housing may include a resin frame and a metal cover which covers the resin frame.
The signal conversion circuitry may include a pin configuration conversion circuit for converting a pin configuration between a first-standard-compliant card and the second-standard-compliant card.
The signal conversion circuitry may include a signal processing circuit for converting signal format between the first-standard-compliant signal and the second-standard-compliant signal to ensure inter-standard compatibility.
The second-standard-compliant card may be a memory card which incorporates therein a memory IC and has a data storage function.
In accordance with the arrangement of the present invention, the housing of the card connection adaptor is formed with the card retaining space having the card insertion port which opens generally perpendicularly to the adaptor insertion direction in which the card connection adaptor is inserted into the first-standard-compliant card slot, and the second-standard-compliant card is inserted into the card connection adaptor from the card insertion port. That is, a card insertion direction in which the second-standard-compliant card is inserted into the card connection adaptor is generally perpendicular to the adaptor insertion direction.
This arrangement prevents the second-standard-compliant card from being inserted into or withdrawn from the adaptor in the adaptor insertion direction. This eliminates the possibility that the second-standard-compliant card is disconnected from the card connection adaptor, and prevents the insertion and withdrawal of the second-standard-compliant card with respect to the card connection adaptor, when the card connection adaptor is fitted in the card slot. Accordingly, an excessively large external force is not exerted on the connector of the card slot. Further, since the active insertion and withdrawal of the second-standard-compliant card with respect to the card connection adaptor can be prohibited, there is no need to provide the guarantee against the active insertion and withdrawal. This ensures easier designing of the card connection adaptor.
The first standard may be a standard which stipulates that an input/output control circuit be provided in a card to be inserted into the card slot.
With this arrangement, the first standard stipulates that the input/output control circuit be present in the card and, therefore, either the card connection adaptor or the second-standard-compliant card should have the input/output control circuit. Where the card connection adaptor has the input/output control circuit, the signal conversion circuitry preferably includes the input/output control circuit.
Examples of cards designed in compliance with standards which stipulate that the input/output control circuit be present in a card include PC cards, CF cards, small PC cards (SPC with exterior dimensions of 42.8xc3x9745xc3x975.0 (mm)).
The signal conversion circuitry may include an input/output control circuit for performing an input/output control with respect to the second-standard-compliant card.
With this arrangement, the input/output control circuit is provided in the card connection adaptor and, therefore, the second standard may be a standard which stipulates that the input/output control circuit be present in the card slot, or a standard which stipulates that the input/output control circuit be present in the card. Examples of cards designed in compliance with standards which stipulate that the input/output control circuit be present in a card slot include SmartMedia cards, MultiMedia cards, Miniature cards, MemoryStick cards and SIM (subscriber identity module) cards.
The second standard may be a standard which stipulates that an input/output control circuit be provided in the second-standard-compliant card.
With this arrangement, the card connection adaptor need not have a data input/output control function. Therefore, the signal conversion circuitry may merely include the pin configuration conversion circuit.
Examples of cards designed in compliance with standards which stipulate that the input/output control circuit be provided in a card include PC cards, Small PC cards and CF cards.
In accordance with another aspect of the present invention, there is provided a card connection adaptor which comprises: a first connector compliant with the first standard; a second connector compliant with the second standard; a housing which holds the first connector and the second connector, the housing having a card insertion port which opens in a direction generally perpendicular to an adaptor insertion direction in which the card connection adaptor is inserted into a card slot, and a card retaining space for retaining therein the second-standard-compliant card inserted from the card insertion port; and an indication mechanism for providing an indication of whether or not the second-standard-compliant card is retained in the housing on a rear face of the adaptor as seen in the adaptor insertion direction (on a face of the adaptor to be located adjacent an opening of the card slot when the card connection adaptor is fitted in the card slot).
Since the card is inserted into the card retaining space of the housing in a card insertion direction which is perpendicular to the adaptor insertion direction, the housing need not have an opening on the rear face thereof. For enhancement of the strength of the housing and prevention of intrusion of foreign matters in the card retaining space, it is preferred that the rear face of the housing is closed.
With such an arrangement, however, it is impossible to check whether or not the second-standard-compliant card is fitted in the adaptor by viewing the opening of the card slot when the card connection adaptor is fitted in the card slot.
In accordance with the invention, the indication mechanism for indicating whether or not the second-standard-compliant card is retained in the card retaining space is provided on the rear face of the housing. Thus, the presence or absence of the card in the adaptor can easily be checked for.
Since the card connection adaptor is constructed such that the indication mechanism per se can be seen from the opening of the card slot, it can easily be checked whether the card connection adaptor or a card compliant with the first standard is connected to the card slot.
The indication mechanism may include a switch member which is operative when the second-standard-compliant card is fitted in the card retaining space, and an indication lamp provided on the rear face of the adaptor as seen in the adaptor insertion direction and adapted to be energized or de-energized by the switch member.
With this arrangement, the switch member is operative in response to the insertion of the card into the card retaining space of the card connection adaptor, whereby the indication lamp is turned on and off. The indication lamp may be powered from an internal power source such as a battery incorporated in the card connection adaptor. When the card connection adaptor is not connected to the card slot, it is easy to check for the presence or absence of the card in the adaptor. Therefore, it is preferred to employ such a construction that the indication lamp is powered from the card slot and the power supply to the indication lamp is effected only when the card connection adaptor is fitted in the card slot.
The indication mechanism may include a displacement member which is displaceable in response to insertion or withdrawal of the card with respect to the card retaining space, and a visual mechanism for allowing visual observation of the displacement of the displacement member from the outside of the housing on the rear face of the adaptor as seen in the adaptor insertion direction.
With this arrangement, the displacement of the displacement member in response to the insertion and withdrawal of the card with respect to the card retaining space can be observed from the outside of the housing by means of the visual mechanism and, therefore, the presence or absence of the card in the card retaining space can easily be checked for.
The displacement member may be, for example, a spring member which is deformable in abutment against the card inserted into the card retaining space. In this case, the visual mechanism includes a window formed in the rear face of the housing, and an indicator member which is displaceable in response to the deformation of the spring member inside the window so as to get into or out of sight from the window. The indicator member is preferably imparted with a conspicuous color (e.g., a color different from the color of the rear face of the housing, or a fluorescent color). Further, the indicator member may be a part of the spring member or a separate member attached to the spring member.
The displacement member may be displaceable in the card insertion direction. In this case, the displacement member may be operative in abutment against a front face of the card.
The displacement member may be displaceable generally perpendicularly to the card insertion direction (e.g., along a line extending through the upper and lower faces of the card-shaped card connection adaptor). In this case, the displacement member may be displaced by either of the upper and lower faces of the card.
The displacement member may include an engagement member which is engageable with an engagement portion formed in a side face of the card, whereby the displacement member is displaced by the insertion or withdrawal of the card.
Further, the indication mechanism may include a card visual mechanism for allowing visual observation of the card retained in the card retaining space from the outside of the housing on the rear face of the adaptor as seen in the adaptor insertion direction.
With this arrangement, the card retained in the card retaining space can be observed from the rear face of the adaptor by means of the card visual mechanism. Thus, a user can perceive the presence or absence of the card in the adaptor.
In this case, the card visual mechanism may include a window extending through the rear face of the housing to the card retaining space. In this arrangement, at least the periphery of the window in the rear face of the housing is preferably imparted with a color which is distinguishable from the color of the card. Further, the visibility may be enhanced by imparting the housing per se with a color different from the color of the card or by imparting a portion of the card opposed to the window with a color different from the color of the rear face of the housing. The visibility may further be enhanced by fitting a lens in the window.
The foregoing and other objects, features and effects of the present invention will become more apparent from the following description of the preferred embodiments with reference to the attached drawings.